1. Field of the Invention
The present invention relates to an inner bladder structure of punching bag; particularly one that using liquid and air simultaneously as filler, and the weight and tactile feel of inner bladder can be adjusted in accordance with user's demand.
2. Description of Prior Arts
Conventional inner bladder structure of punching bag is shown in FIG. 1; the foregoing conventional inner bladder is a closed inner bladder using solid (such as sand), liquid (such as water), or gas (such as air) as filler 30 and placed inside one external bag 20.
It is easy and cheap to obtain said filler 30; however, the weight of punching bag impacts on the training effect. When solid is used as filler 30 in inner bladder, the punching bag is heavy and therefore cannot be easily moved and stored. When liquid is solely used as filler 30 in inner bladder, the heaviness of punching bag would result in poor training effect. When gas is used as filler 30 in inner bladder, the punching bag is generally too light in weight and requires other accessories to fix it in place, thus result in poor training effect.
In addition, for conventional punching bag structure, be it adopting solid, liquid, or gas as filler 30, there is only one tactile feel. When filling with solid, punching bag gives a firm texture while filling with liquid adds some softness and resilience. When filling with gas, punching gas is even more resilient. However, none of the foregoing fillers can be adjusted in the structure to create different textures to satisfy user's different training demand.
Thus, there are foregoing drawbacks of conventional inner bladder structure in prior art to be improved.